THE CURRENT STATUS OF MYOCARDIAL REVASCULARIZATION - CHANGING TRENDS AND RISK FACTOR-ANALYSIS

From November 1989 to December 1994, we performed 2264 bypass procedur es. Data were collected prospectively. The population was divided into three subgroups: group 1 = single internal mammary artery (IMA) +/- v eins (n = 1584); group 2 = veins only (n = 503); and group 3 = two or more arterial conduits +/- veins (n = 177). Patients who received only saphenous vein conduits (group 2) were significantly older (66.7 +/- 8.9 years) than either group 1 (60.3 +/- 8.3 years) or group 3 (51.6 /- 9.2 years). Furthermore, this cohort group had the highest percenta ge of females (28.5%), urgent cases (43.5%), preoperative myocardial i nfarction (MI) (18.5%), and redo surgery (5.4%). In contrast, patients who received two or more arterial conduits were 94.9% male, and had t he lowest incidence of urgent cases (18.1%) and redo surgery (0.5%). M ortality was 1.4% in group 1 and 3.2% in group 2; there were no deaths in group 3. Furthermore, group 2 patients had the highest incidence o f perioperative MI (6.6%), low output syndrome (22.1%), intra-aortic b alloon pump (IABP) assist (6.2%), and stroke (2.7%). By multivariate l ogistic regression analysis (odds ratio in parentheses), redo surgery (7.92), preoperative IABP (5.53), poor LV function (4.01), renal impai rment (3.94), and advanced age (2.12) were all predictors of operative mortality. When mortality and morbidity (death, infarction, low outpu t syndrome, IABP assist) were combined, regression analysis revealed t hat in addition to the above variables, female gender and cold cardiop legia were also independent predictors of combined mortality and morbi dity. Resource utilization was determined far the three patient groups . There was concern that the increased technical demands of multiple a rterial grafting along with longer periods of aortic occlusion and pum p times may lead to increased complications and prolonged hospital sta y. However, we found that group 3 had the lowest ventilation time, int ensive care unit stay, and hospital stay. The results no doubt were in fluenced by case selection. Whether or not this approach to revascular ization will increase long-term survival and freedom from reoperation will require further study.